AEGIS Type Naval Air Defense in the 1960s?

[Delta Force]

Typhon was an air defense system the United States Navy was working on in the early 1960s as a replacement for the Talos, Terrier, and Tartar missiles. It would have consisted of two AN/SPG-59 radar variants (one for cruisers, one for destroyers), as well as two missile types, the Bendix SAM-N-8/RIM-50 Typhon LR and the Bendix SAM-N-9/RIM-55 Typhon MR. It was essentially the predecessor to AEGIS.

Ultimately, Typhon was abandoned because it lost too much signal strength during signal processing, resulting in the radar's maximum range being less than the minimum needed for target resolution. While I am unsure if signal processing refers to something having to do with the signal itself, or the processing computers chosen not being up to the task, there were quite a few 1960s and 1970s radar systems that failed to function either because the radar couldn't pick things up (the Nike missile had enough performance to hit targets the radar couldn't detect due to speed) or there wasn't enough processing power (Sentinel/Safeguard).

There were advanced computers and radars that were functioning around the time Typhon was being developed, so whatever the issue was, it seems it would have been possible to resolve. For radars, the Royal Navy had the successful Type 984 set, and was planning a transistorized and possibly AESA version of it as the Type 985. The Type 984 also had an advanced command and control system that allowed it to both search and track using the same system as part of the Comprehensive Display System. Another advanced radar is the Anglo-Dutch Type 988, which was planned for the Royal Navy CVA-01 aircraft carriers and Type 82 destroyers, and ultimately saw service on the Dutch Tromp class frigates/destroyers. The Royal Canadian Navy and United States Navy also were developing systems to try to allow for integrated systems across ships, respectively DATAR and the Naval Tactical Data System. On land the United States Air Force and Army worked together with Canada to field the Semi-Automatic Ground Environment system, which allowed for centralized command and control of interceptors and missiles and integrated information from ground, air, and sea based radar systems.

It seems that many of the components necessary for a workable AEGIS type system would have been available in the 1960s, well before the first AEGIS cruiser, USS Ticonderoga, entered service in the early 1980s. So, would it have been possible? If so, how does this butterfly naval air defense, seeing as the premier naval aircraft of the 1960s and 1970s were interceptors for defending the carrier battle group?

 

[pathology_doc]

Points to bear in mind:


1) Count SAGE out at once. As a land based system, it benefited from having essentially no limitations on space or power consumption, plus important issues of serviceability at sea do not enter SAGE's equation either. There can be no better example of an apples-to-oranges comparison.


2) Continuing from the above, building a valve or transistor-based system becomes hideously complicated when you need to build it small enough to take it to sea. Complexity is inversely proportional to reliability AND serviceability, at least until the point where line-replaceable units become commonplace and Mean Time Between Failures exceeds the length of a deployment (and even then, how many LRUs do you take to sea? A whole system's worth? Impractical.)


3) A search-track-display system for a combat information/action data centre in a flagship is NOT the same as a fully integrated fire control system that will provide azimuth/elevation control for missile directors, handle command-guidance and/or mid course update signals as and where appropriate, and - depending on the system - even do things like deciding which particular missile to pick off the rack, where to align the launcher, gather a missile into an initial wide-angle guidance beam, etc. etc.


The general gist I got reading Friedman's "US Naval Weapons" was that Typhon was technically do-able, but it was also extremely expensive to put in a warship and would do nothing more than create yet another high-value target within the task group, almost as unpleasant to lose as the carriers around which the groups were built. The missiles were works of art, true, but the system to fire and guide them was economically unsupportable for the number of escorts required, even for the cold-war US. France and Germany spent most of the latter half of the 19th Century and the early part of the 20th gearing up for a war which was almost inevitable and which it could be argued that both sides secretly wanted. The US's preparations were for a war so horrific it hoped NEVER to have to fight it, so having a prohibitively expensive fleet in being for an indefinite period of time wasn't a game it could play.


However, electronic and missile technology were such rapidly evolving fields that ten years later, the absurdly expensive became the eminently possible. Now we can do things with a Standard-ER sized missile that Talos or even Typhon could never have managed, even if they hadn't been primarily air-breathers. God only knows what might be accomplished with a Talos airframe these days, although of course being an air-breather would preclude it from being anything other than a last-ditch ABM defence.


That the components existed is without doubt - it's integrating them into a unified, affordable and reliable package that was the impossible dream in the sixties. The other thing to bear in mind is that the missile defences are and always have been only part of the task group/convoy air defence package. It was always thought of as a layered system - interceptors far out, missiles closer in. What Typhon would have done is to move the junction of the two zones outward and upward while making kills within the missile zone a more reliable proposition. This might potentially have the effect of favouring interceptor designs with a higher transit speed (to get to their zone of operations as fast or faster) and greater endurance (your CAP has to loiter further from the carrier). Either way you burn more jet fuel, so maybe that favours an earlier shift to nuclear power for carriers, so there's more internal space available for jet fuel rather than their own, and it might also mean one or two more refuelling aircraft on each carrier deck, and so on... It's hideously complex.

 

[Delta Force]

I think a single SAGE computer could handle the air defenses for the entire NORAD region, so that might be overkill at sea. Could a smaller system have been used that would have been suitable for the needs of a Navy battle group, and perhaps more rugged and reliable for operations at sea? Historically SAGE got around the reliability problems by having two computers in the same building that could be switched around, but having two computers on one ship might not be an option.

 

[pathology_doc]

I suspect not. By the time you water it down to something you can take to sea, what you've got is probably no better than what the fleet had anyway.


Innumerable contemporary and futuristic scenarios have been written around what happens when a central combat control system is either hacked, jammed or destroyed. There's a reason for that.

 

[sferrin]

I think a single SAGE computer could handle the air defenses for the entire NORAD region, so that might be overkill at sea. Could a smaller system have been used that would have been suitable for the needs of a Navy battle group, and perhaps more rugged and reliable for operations at sea? Historically SAGE got around the reliability problems by having two computers in the same building that could be switched around, but having two computers on one ship might not be an option.

Do you know how big a single SAGE computer was?

http://www.extremetech.com/computing/151980-inside-ibms-67-billion-sage-the-largest-computer-ever-built

 

[Delta Force]

I suspect not. By the time you water it down to something you can take to sea, what you've got is probably no better than what the fleet had anyway.


Innumerable contemporary and futuristic scenarios have been written around what happens when a central combat control system is either hacked, jammed or destroyed. There's a reason for that.

SAGE itself was quite vulnerable to jamming until the early to mid-1960s. A Navy air defense system would probably have been designed with electronic warfare in mind, given the problems the Air Force had retrofitting those capabilities back to SAGE.

I think a single SAGE computer could handle the air defenses for the entire NORAD region, so that might be overkill at sea. Could a smaller system have been used that would have been suitable for the needs of a Navy battle group, and perhaps more rugged and reliable for operations at sea? Historically SAGE got around the reliability problems by having two computers in the same building that could be switched around, but having two computers on one ship might not be an option.

Do you know how big a single SAGE computer was?

http://www.extremetech.com/computing/151980-inside-ibms-67-billion-sage-the-largest-computer-ever-built

Something smaller would obviously have been capable of handling fleet air defense operations. If needed though, there were several World War II vintage aircraft carrier hulls that could have been converted for carrying computers and electronics. The computers and radars required for this would fall somewhere between the interceptor and AWACS systems on the small end, and SAGE on the large end.

 

[Hobbes]

A big obstacle to developing an AEGIS-like system earlier is missile control. Back then, each missile needed a dedicated radar director. You can fit a limited number of them on a ship, which limits the number of missiles you can control. Typhon tried to get around this by using a single phased array for search, tracking and direction. They couldn't get this to work reliably back then. Its successor (of sorts), the AN/SPS-32 and AN/SPS-33 combo, wasn't great in that regard either (and omitted the missile direction function).

One of the innovations in AEGIS was that the missiles became smart enough that you could control several missiles from one director (time sharing). Getting that capability earlier would mean you need really large missiles to fit all the electronics.

Only now are we getting systems (e.g. Signaal APAR) that combine search, tracking and direction in one radar.

 

[JFC Fuller]

Like Talos? ;D

Which proves Hobbes' point. Talos used separate missile guidance and target tracking radars rather than a single dedicated unit which meant that is was possible to time-share system components (the target tracking radars that were only required for the end game) between multiple inflight missiles (the USN called it multiplexing at the time) but this was only really practical at longer ranges and the separate radars made for an even more space and power intensive system. Thus, whilst the Talos system was theoretically capable of engaging multiple targets through its fire channels the target tracking radar itself was not.

The brilliance of Aegis is that its compact and power frugal enough to be put on reasonably sized (full systems are on ships down to about 6,000 tonnes) gas turbine powered vessels which means it can be deployed throughout the fleet (for the USN) as a destroyer system rather than requiring some exotic cruiser project (as both Talos and Typhon required); hence why the Ticonderoga class could be built on a destroyer hull (and was originally designated as a destroyer) with a destroyer propulsion plant. In that context Aegis was an outstanding technical achievement and I would go out on a limb and say it was twenty years before any other navy took something as technically impressive to sea.

 

[sferrin]

Like Talos? ;D

Which proves Hobbes' point. Talos used separate missile guidance and target tracking radars rather than a single dedicated unit which meant that is was possible to time-share system components (the target tracking radars that were only required for the end game) between multiple inflight missiles (the USN called it multiplexing at the time) but this was only really practical at longer ranges and the separate radars made for an even more space and power intensive system.

It was a joke. Hence the ;D Just pointing at, at one time, the USN had some huge SAMs (though not practical for smaller ships).